Hi Patrick, and welcome! Checking the CAPS LOCK key is always the first thing to check as it is an easy mistake to make. Going back over the link that
@CptCharis provided, I see that user
@Greentea never responded with a solution (and he/she also never mentioned what kind of computer they were using).
So, with a sudden "AHA!" moment just now, knowing that you are using a netbook, I looked up your Samsung and see that it has a similar keyboard to an Acer netbook that I have. And if CAPS LOCK is not your problem, then I think I know what it might be as it has bitten me before too.
Look along your keys on the right side of the keyboard... note that many of them have a secondary function. If the Samsung N150 photo I'm looking at matches yours, then the letter U also equals 4. The letter I also equals 5. The letter O also equals 6. And so on. These alternative keys are also on P, J, K, L, and M.
On my Acer, these secondary keys are activated with the
Fn key (next to the Windows Logo key). But what happens sometimes is that these secondary keys are activated by default as primary keys instead.... causing you to mistype your password. For example, if your password was "like" but the secondary keys are active... then you end up typing "352e" but you don't see the characters when entering a password. Fun stuff, right? You could probably type "
Fn-l,
Fn-i,
Fn-k, e" and it would unlock your screen.
The solution on my Acer is to hit
Fn-NumLock keys to toggle the secondary keys back to the secondary status. I hope that will work for you also. If not, Google will probably help us find the method to toggle the keys on the Samsung.
Cheers